Chip forming apparatus



Nov. 7, 1967 Filed June 24, 1965 c. F. SCHNEIDER 3,350,971

CHIP FORMING APPARATUS 2 Sheets-Sheet 1 INVENTOR CHARLES F. SCHNEIDER BY M 6 ATTORNEY Nov. 7, 1967 c. F. SCHNElfDER CHIP FORMING APPARATUS Filed June 24, 1965 2 Sheets-Sheet CONTROL AIR CONV- MOTOR -34 54 I f I SPEED vAR I. coNTRoL SPEED #33 H DRIVE I #I SPEED TRANS- 32 %I%%R 45 J 4 SPEED v CONNECTIONS CONTROL -SPEED MECHANICAL H DRIvE PNEUMATIC, m

I #2 SPEED TRANS.

cAL. SPEED RATIO RoLL TRANS.- RELAY CHOPPER MOTOR #l 58 59 70 H 1 r vARI- RATIO cYcLE :SPEED i SPEED -38 RELAY CIRCUIT CONTROL DRIvE H I #3 SPEED TRANS. E

CHOPPER MOTOR #I 73 74 75 H I I VARI- RATIO cYcLE SPEED SPEED 49 RELAY CIRCUIT "CONTROL DRIVE H l #4? SPEED TRANS. [53* PRESS GAUGE 7] OUTPUT 60 6| 63 67 Q TgllED INVENTOR S938 CONTROL cI-IARLES F. SCHNEIDER ATTORNEY United States Patent 3,350,971 CHIP FORMING APPARATUS Charles F. Schneider, Lancaster, Pa., assignor to Armstrong Cork Company, Lancaster, Pa., a corporation of Pennsylvania Filed June 24, 1965, Ser. No. 466,669 9 Claims. (Cl. 83354) This invention relates to chip forming apparatus and more particularly to chip forming apparatus including a plurality of choppers and a control system therefor to provide chips of various shapes and sizes. A first chopper divides a sheet material into a plurality of long thin pieces and is capable of varying the width of the long thin pieces due to a control which changes the relative speed between the feed and the chopper. The long thin pieces drop upon a second feed structure which moves the thin pieces towards a second chopper. The second chopper separates the long thin piece into a plurality of small chips. The length of the chips may be varied based upon any change in the relative speed between the feed and the chopper. The apparatus is further capable of having the relative speed between the feed and chopper varied continuously during the cutting operation so that the width of the long thin piece and the length of the chips can be constantly varied during the chip forming procedure. Consequently, the system provides chips of various shapes and sizes. The relative speed relationship is secured by the use of pneumatic speed transmitters which cause a speed control to vary sinusoidally to provide the various sized and shaped chips.

Many of the chip producing devices of the prior art include slitting and chopping mechanism which act on sheet material to produce chips of a uniform size and shape. Examples of such devices are shown in U.S. Patents 2,316,283, 2,335,515, 2,508,414, 2,655,213; etc. Several of the devices shown in these patents relate to plastic chip forming. Such chips are utilized in many areas including the fields of decorative, resilient floor and wall coverings. In this field, variation in design techniques is continually sought in order to satisfy the demands of the market with regard to new designs.

Some of the designs in floor and wall coverings utilize a combination of chips which have been fused into a sheet or tiles. This material may or may not have a backing. The chips may be irregular or regular, in contacting relationship with one another, spaced from one another, in overlying relationship with one another, or distorted to produce various design efifects. In some cases, these chips are held in sheet form by granular dry blend material which has been fused with the chips to form a sheet as shown in U.S. Patent 3,056,224. It was found that a wide variation in shape and size of chip could be obtained by using chopping apparatus and the control system disclosed hereinafter.

It is an object of the present invention to provide chip forming apparatus which is capable of producing chips of various shapes and sizes.

It is another object of the present invention to provide chip forming apparatus having chopping means and control means therefor to produce chips of varying shapes and sizes.

Other objects of the present invention will be readily apparent from the detailed description thereof with reference to the drawings wherein:

FIGURE 1 is a view in elevation of an embodiment of chip forming apparatus according to the present invention;

FIGURE 2 is a plan view of the apparatus shown in FIGURE 1;

FIGURE 3 is a side view in elevation of the apparatus shown in FIGURE 1;

FIGURE 4 is a control circuit diagram which may be used with the apparatus shown on FIGURES 1 to 3; and

FIGURE 5 is a pneumatic cycling circuit diagram of cycling circuit apparatus which may be used with the circuit shown in FIGURE 4.

Referring now to FIGURE 1, there is shown a mix preparation unit 20 which includes a Banbury mixer to prepare vinyl plastic composition 21, for example, which is to be processed into sheet form. This vinyl resin composition may take the form of that set forth in U.S. Pattents 2,913,773 or 3,000,754. Such composition 21 is usually granular in form and is deposited from the mix preparation unit 20 into the nip 22 between calendering rolls 23 and 24, which may be of a conventional nature such as that shown in U.S. Patent 2,508,414, for example. The calender rolls 23 and 24 may be provided with a conventional motor 25, conventional, variable speed drive means 26, and suitable heating and/or cooling fluids to properly fuse the granular mix 21 and squeeze it into sheet form 27 in the nip 22 between said rolls, as is well known in the art. The temperatures of the fluids in the calendering rolls 23 and 24 are so adjusted in the conventional manner that the sheet material as it leaves the nip 22 will remain adhered to calender roll 24 while being stripped from roll 23. Conventional doctor blade means 28 or other stripping mechanisms may be used to strip the calendered sheet 27 from roll 24 into contact with conveyor 29.

Conveyor 29 is supported on idler rollers 30 and 31 and is driven by power roller 32. Roller 32 is driven through a conventional, variable speed drive 33 by means of a conventional motor 34. Conveyor 23 carries vinyl sheet 27 over support 35 which has its outermost edge adjacent rotary chopper 36 in cutting relationship with blades 37 mounted thereon. Chopper 36 is driven through conventional, variable speed drive unit 38 by means of conventional motor 39. It will be apparent that as sheet 27 is fed over support 35 into the path of chopper blades 37 as they are rotating about an axis transverse to conveyor 29 in cutting relationship with said support 35, sheet 27 will be separated into strips 40.

Underlying support 35 and chopper 36 is conveyor 41 having its longitudinal axis substantially transverse to the longitudinal axis of conveyor 29.. Conveyor 41 is supported on idler roller 42 and drive roller 43. Roller 43 is driven through conventional, variable speed drive 44 by means of conventional motor 45. As sheet 27 is separated into strips 40 by chopper 36, said strips 40 will fall onto the surface of conveyor 41 direction indicated by the arrows.

Adjacent the leading end of conveyor 41 block 46. Support block 46 has an outer edge conveyor 41, which outer edge is adjacent is support away from chopper 47 whose blades 48 are rotated in cutting relationship past the outer edge of block 46. Chopper 47 is connected through conventional, variable speed means 49 to conven' tional motor 50. As conveyor 41 is driven toward support block 46, the strips 40 of sheet material carried thereby will be moved over support block 46 through chopper 47, whereupon said strips 40 will be separated into chips 51. It is apparent that if all the drive motors and variable speed drives are driven at fixed speeds, chips of substantially uniform size and shape will be produced. In the case of the apparatus shown in FIGURES 1 to 3, such chips will be rectangular in shape.

It was found that variation of one or both of the chopper speeds would produce irregularly shaped and sized chips. Further variation in the size and shape of chips could be obtained by varying the speed of the feed conveyors. However, it was found that adequate variation to be carried thereby in a in size and shape of chips could be obtained through.

variation in chopper speed.

In FIGURE 4 there is shown a circuit diagram for accomplishing the variation in chopper speed necessary to produce various sized and shaped chips. The control circuit shown in FIGURE 4 is basically pneumatic in nature. A conventional pneumatic speed transmitter 52 is connected to calender roll 24. Speed transmitter 52 may be of the type marketed by the Foxboro Company bearing the identification number 16A. Such a device measures speed and converts it into a pneumatic signal. This device has a shaft which may be connected through suitable drive means to the shaft of the calender roll 24. The speed transmitter 52 may be calibrated to modify pres surized control air received from a suitable source and produce an output signal between 3 psi. and psi. with the minimum r.p.m. which is to be measured corresponding to the 3 p.s.i. rating and the maximum rpm. to be measured corresponding to the 15 p.s.i. rating. A pressurized supply of control air at 20 psi, for example, is supplied to the speed transmitter 52. The control air is modified by the speed transmitter 52 in response to variations in speed of the calender roll to provide the aforementioned output signal of between 3 psi. and 15 psi.

The output signal from speed transmitter 52 is communicated through suitable conduit means to a conventional ratio relay or pneumatic ratio unit 53 which receives pressurized control air from a suitable source, modifies it, and puts out a pneumatic signal which is always the same fraction or multiple of the pneumatic input signal which it receives. Such a relay is marketed by Moore Products Company under model #54441.

The output signal from ratio relay 53 is transmitted through suitable conduit means to speed control unit 54 Which may be of a conventional type known as a remote set speed control such as that marketed by Bristol Company, Model 650. Such a speed control 54 functions to receive a pneumatic signal from a director and compares the received signal with a measured signal. The unit then makes suitable adjustments and modifies pressurized control air which it receives from a suitable source to provide an output signal which will tend to bring the measured signal in conformity with the directed signal. In the case of speed control 54, the directed signal is that received from ratio relay 53. The measured signal is that received from speed transmitter 55 which may be the same type as speed transmitter 52. Speed transmit ter 55 is mechanically connected to variable speed drive 33 to measure the speed thereof and convert said speed into a pneumatic signal which is transmitted to the speed control unit 54. The output signal of speed control unit 54 is transmitted to variable speed drive 33 which contains a conventional air cylinder to receive the output signal from the speed control unit 54 and mechanically vary the speed of the drive 33 in a manner directly proportional to the signal received from speed control unit 54. As stated above, the speed control unit 54, in effect, compares the actual speed of the output shaft of the variable speed drive unit 33 with a pneumatic signal representing the speed at which said variable speed drive output shaft should be running and makes any necessary speed corrections if the measured speed is not in conformity with the proper speed as determined by the speed transmitter 52 and ratio relay 53.

The output signal from ratio relay 53 is also communicated to speed control 56 which is the same type unit as speed control 54. Speed control 56 is connected to receive the pneumatic signal put out by speed transmitter 57 which is mechanically connected to the output shaft of variable speed drive 44. Speed control 56 and speed transmitter 57 operate to control the output speed of variable speed drive 44 in the same manner that speed control 54 and speed transmitter 55 operate to control the output shaft of variable speed drive 33 described above.

The output signal from ratio relay 53 is conducted to a similar ratio relay 58, the output of which is communicated to the cycling circuit 59. The details of circuit 59 are shown in FIGURE 5. As shown in FIGURE 5, the output signal from ratio relay 58 may be transmitted through pneumatic conduit means 60 to valve 61. Conduit 62 connects valve 61 and valve 63. A pneumatic conduit 64 communicates conduit 62 with derivative control unit 65, which is of a conventional nature such as that marketed by Moore Products under model number 59. This derivative unit 65 is supplied with pressurized control air which is converted into an output signal. This output signal is caused to vary according to the rate of the change of the input such as that received through conduit 64. Thus, if the input signal is absolutely steady, the output signal will also be steady. However, if the input pneumatic signal varies, the output signal from the derivative unit 64 will vary according to the rate of change thereof. The output signal from derivative unit 65 is communicated through conduit 66 to conduit 67. Conduit 67 intercommunicates valve 63 with accumulator 68. A conduit 69 communicates with accumulator 68 and leads to speed control 70. A pressure gauge 71 may be provided in conduit 69. Speed control 70 may be of the same type as speed controls 54 and 56. The output signal of speed control 76} is communicated to a conventional speed control pneumatic cylinder associated with variable speed drive 38. Speed transmitter 72 may be of the same type as speed transmitters 55 and 57 and is connected mechanically to the output shaft of variable speed drive 33. Speed transmitter 72 converts the speed of the output shaft of variable speed drive 38 into a pneumatic signal which is transmitted to speed control 70. Speed control 70 compares this signal with the signal received from the cycling circuit 59, and if the signals are not in conformity, speed control 70 makes suitable corrections in the speed of variable speed drive 38 by means of a pneumatic output signal transmitted to the pneumatic control cylinder of variable speed drive 38. Thus, the speed control 70, and speed transmitter 72 control variable speed drive 38 in the same manner as the speed control 54 and speed transmitter 55 control variable speed drive 33.

However, the signal received by speed control 70 may be caused to vary sinusoidally by appropriate adjustment of the cycling circuit 59. Referring to FIGURE 5, derivative unit 65 may be adjusted along with valves 61 and 63 such that said unit 65 will become unstable and provide a continuously varying output in response to very slight variations in input. Such slight changes are almost always present in conventional pneumatic systems. Valves 61 and 63 and the accumulator 68 function to cause delays and continuously varying pressure conditions on either side of the derivative unit 65. The continuously varying conditions will cause the derivative unit to continuously cycle in the sinusoidal manner heretofore mentioned.

Referring to FIGURE 4, there is shown a similar control circuit for variable speed drive 49. In this case, ratio relay 73 may be the same type as and communicates with ratio relay 53. The output of ratio relay 73 may be communicated with a cycling circuit 74 which may have the same components shown in the cycling circuit 59 illustrated in FIGURE 5. The output of cycling circuit 74 is connected to speed control 75 which is in turn connected to variable speed drive 49 and speed transmitter 76. This circuit may operate in the same manner as that circuit controlling variable speed drive 38, and the corresponding elements in each circuit may operate in a similar manner.

Thus, it is apparent that the choppers 36 and 47 may be coordinated with the speed of the calender rolls 23 and 24. It is to be understood that all of the control components including speed transmitters, ratio relay units, speed control, cycle circuits, derivative units, etc. are adjustable in nature and may be varied to suit changing conditions. In any event, it is apparent that the choppers 36 and 47 may be varied sinusoidally and controlled in relationship to the calender rolls. It is also noted that the conveyor speeds may be controlled in response to the speed of the calender rolls with the circuits heretofore described. The variation of the chopper speeds provides chips of varying shapes and sizes as mentioned above. It is noted that the frequency, amplitude, and period of the sinusoidal, pneumatic signal may be varied. Any one of these variables may be used to change the size and/ or shape of the chips. Further, the speeds of the conveyors may be varied as well as the angles of feed of the sheet material and strips if so desired. It will be apparent that the extent of adjustment of these variables may have a cumulative effect on the variation in size and shape of chip. Thus, if the frequency, amplitude and period of each chopper as well as the speed of the conveyors are set at different values, the possibility of obtaining two chips of the same shape and size during a given period of operation is quite small. In certain applications such as mosaic designs for use in the floor covering industry, for example, such variation may be desirable. However, it is also apparent that the control system disclosed herein may be used to manufacture chips of the same size or of slightly differing sizes and shapes. A broad range of variability is afforded with the apparatus control system of the present invention.

It is to be understood that the present invention is not limited to the specific embodiment shown and described herein, and that various changes may be made. As mentioned above, the position of the choppers with respect to the feed conveyors may be varied such that the sheet material and/or strips may be fed to the choppers at various angles. It is to be understood that the particular drive means are of a conventional nature and other known drives may be used. For example, the variable speed drives may be omitted, and variable speed motors may be directly connected to the appropriate components, in which case the variable speed motor would be provided with suitable and conventional electrical controls which would be actu ated by a pneumatic cylinder. This cylinder would receive the speed control signal from the appropriate speed control unit. The size, shape, location, etc., of the various components may be varied. It is noted that portions of the disclosed control circuit may be used with conventional apparatus other than the dual chopper arrangement disclosed herein. For example, the variable control principles set forth herein may be utilized with a single chopper or a conventional dicer, for example. In the case of the dicer, the cycling circuit shown in FIGURE 5 may be used to vary the speed of the rotating knives.

It will be apparent that the apparatus of the present invention provides efficient means for producing chips of varying shapes or sizes.

Various modifications will occur to those skilled in the art without departing from the spirit and scope of the invention as defined in the claims.

I claim:

1. Chip forming apparatus comprising first sheet material supply means, means for separating said sheet material into strips, means for separating said strips into chips, means for controlling said sheet material supply means, said sheet material separating means, and said strip separating means, said controlling means including means for varying continuously during the operation of said apparatus the sheet material supply means, said sheet material separating means, and said strip separating means whereby size of said chips may be varied during operation of said apparatus.

2. Chip forming apparatus comprising first rotary chopper means, first variable speed drive means for said first chopper means, means to feed sheet material through said first chopper means to separate said sheet material into strips, second rotary chopper means, second variable speed drive means for said second chopper means, means to feed said strips through said second chopper means to separate said strips into chips, control means including means to cause at least one of said first and second variable speed drive means to vary the speed of at least one of said first and second chopper means during operation thereof.

3. Chip forming apparatus according to claim 2 wherein said control means include means to vary the speed of at least one of said chopper means continuously.

4. Strip forming means according to claim 3 wherein said control means include means to cause one of said chopper speeds to be varied sinusoidally.

5. Strip forming apparatus according to claim 2 wherein said control means include means to cause both of said speeds to be varied continuously during operation thereof.

6. Chip forming apparatus according to claim 5 wherein said control means include means to vary both said speeds sinusoidally.

7. Chip forming apparatus according to claim 2 wherein said control means include pneumatic control circuit means.

8. Chip forming apparatus according to claim 7 wherein said pneumatic control circuit means include means for controlling said sheet material feeding means and said strip feeding means.

9. Chip forming apparatus according to claim 1 Wherein said separating means are choppers, and the means for varying continuously the operation of the apparatus will vary chip size by varying the relative speed of either one or both choppers relative to the feed speed.

References Cited UNITED STATES PATENTS 2,776,711 1/1957 Bas 83-408 X 3,066,562 12/1962 Barnett et a1 83-l58 X 3,302,502 2/1967 Geyer 83-44 ANDREW R. JUHASZ, Primary Examiner. 

1. CHIP FORMING APPARATUS COMPRISING FIRST SHEET MATERIAL SUPPLY MEANS, MEANS FOR SEPARATING SAID SHEET MATERIAL INTO STRIPS, MEANS FOR SEPARATING SAID STRIPS INTO CHIPS, MEANS FOR CONTROLLING SAID SHEET MATERIAL SUPPLY MEANS, SAID SHEET MATERIAL SEPARATING MEANS, AND SAID STRIP SEPARATING MEANS, SAID CONTROLLING MEANS INCLUDING MEANS FOR VARYING CONTINUOUSLY DURING THE OPERATION OF SAID APPARATUS THE SHEET MATERIAL SUPPLY MEANS, SAID SHEET MATERIAL SEPARATING MEANS AND SAID STRIP SEPARATING MEANS WHEREBY SIZE OF SAID CHIPS MAY BE VARIED DURING OPERATION OF SAID APPARATUS. 